WO2021235388A1

WO2021235388A1 - Furnace monitoring device

Info

Publication number: WO2021235388A1
Application number: PCT/JP2021/018592
Authority: WO
Inventors: 直樹佐藤; 辰朗田之上
Original assignee: 株式会社Ihi
Priority date: 2020-05-18
Filing date: 2021-05-17
Publication date: 2021-11-25
Also published as: JPWO2021235388A1; US20230168037A1; AU2021275268B2; AU2021275268A1; DE112021002810T5

Abstract

This disclosure relates to a furnace monitoring device (A) including: an imaging device (1) for photographing combustion ashes adhered to a monitor location in a furnace (X); evaluation systems (2, 3) for evaluating the adhesion situation of the combustion ashes according to a monitor image output by the imaging device (1); and a notification device (4) for notifying information about the combustion ashes according to the evaluation result of the evaluation systems (2, 3).

Description

Fire furnace monitoring device

This disclosure relates to a furnace monitoring device. This application claims priority based on Japanese Patent Application No. 2020-086657 filed in Japan on May 18, 2020, the contents of which are incorporated herein by reference.

The following Patent Document 1 discloses an in-core monitoring device that takes a picture of the inside of a boiler in a furnace with a monitoring TV camera and monitors the inside of the furnace based on the image. This in-furnace monitoring device supplies the light of the light source to the light projecting lens via the light projecting optical fiber, and provides an in-core imaging optical fiber between the light projecting lens and the monitoring TV camera. , The condition inside the furnace is confirmed even when the inside of the furnace is dark.

Japan Minor Kaisho 60-8647A Gazette

By the way, the above-mentioned background technology is for monitoring the inside of the furnace of the boiler by using a TV camera for monitoring, but it is not intended to monitor the state of combustion ash, but to monitor the bottom of the furnace. It is a thing. As is well known, in boilers, ash (combustion ash) produced by burning fuel adheres to heat transfer tubes in various places. In the technical field of boilers, fuels that are difficult to adhere to such combustion ash are selected, combustion ash is artificially removed, and / and additives are injected.

However, there is a limit to such conventional measures against combustion ash. Especially in recent years when the types of fuels are increasing, it is extremely difficult to take effective measures against the adhesion of combustion ash for each fuel.

The present disclosure has been made in view of the above-mentioned circumstances, and an object of the present disclosure is to provide a furnace monitoring device capable of evaluating the adhesion state of combustion ash more effectively than before.

In order to achieve the above object, the first aspect according to the present disclosure is an image pickup device for photographing the combustion ash adhering to the monitoring point in the furnace, and the combustion ash based on the monitoring image output by the image pickup device. It is a furnace monitoring device including an evaluation device for evaluating the adhesion state and a notification device for notifying the combustion ash based on the evaluation result of the evaluation device.

In the second aspect of the present disclosure, in the first aspect, the furnace is a boiler combustion furnace.

In the third aspect of the present disclosure, the monitoring point is a superheater in the second aspect.

In the fourth aspect according to the present disclosure, in any one of the first to third aspects, the monitoring point is around the burner provided in the furnace.

A fifth aspect according to the present disclosure is, in any one of the first to fourth aspects, the image pickup apparatus is an infrared camera that excludes a flame and captures the combustion ash.

According to the present disclosure, it is possible to provide a furnace monitoring device capable of evaluating the adhesion state of combustion ash more effectively than before.

It is a block diagram which shows the functional structure of the furnace monitoring apparatus which concerns on one Embodiment of this disclosure. It is a schematic diagram which shows the monitoring state around a burner in one Embodiment of this disclosure. It is a flowchart which shows the operation of the furnace monitoring apparatus which concerns on one Embodiment of this disclosure.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
The furnace monitoring device A according to the present embodiment monitors the combustion furnace of the boiler. That is, the furnace X in this embodiment is a boiler combustion furnace.

As shown in FIG. 1, the boiler has a curved shape when viewed from the front, and is a facility that generates steam by using heat (combustion heat) obtained by burning a predetermined fuel. This boiler is, for example, equipment installed in a power plant, and generates steam as a working fluid for driving a steam turbine. Such a boiler includes, for example, a boiler wall x1, a plurality of burners x2, a superheater x3, a reheater x4, a preheater x5, and a bent portion x6.

The boiler wall x1 is a plate-shaped member that forms the outer shape of the boiler, and is formed on a flat plate by joining a plurality of heat transfer tubes in parallel to each other. Water flows from one end to the other end of the plurality of heat transfer tubes forming such a boiler wall x1. This water is heated by the above-mentioned combustion heat, and a part of it becomes steam.

As shown in the figure, a plurality of burners x2 are provided in a part of such a boiler wall x1 to form a combustion chamber R. That is, in the boiler shown in FIG. 1, the left side portion of the bent portion x6 constitutes a combustion chamber R in which fuel burns, and a plurality of burners x2 are provided in the vicinity of the lower end portion. The combustion chamber R has a rectangular shape in a horizontal cross section.

A plurality of burners x2 are each provided on a boiler wall x1 that forms a combustion chamber R and faces in parallel. That is, the plurality of burners x2 are provided so as to face each other. On one of the pair of boiler walls x1 facing in parallel, for example, as shown in FIG. 2, a plurality of (3) burners x 2 in the vertical direction and a plurality (6) burners x 2 in the horizontal direction are provided. Further, the other of the pair of boiler walls x1 is also provided with a plurality of burners x2 arranged in the same manner as the above one.

The installation form of the burner x2 shown in FIG. 2 is just an example. The boiler can take various installation forms of the burner x2 depending on the scale, application, and the like. For example, a plurality of burners x2 may be arranged and installed in a predetermined form only on one of a pair of boiler walls x1 facing in parallel.

Such a plurality of burners x2 inject fuel such as pulverized coal and biomass supplied from a fuel supply system (not shown) into the combustion chamber R, and the combustion air separately taken into the combustion chamber R by the air supply system is injected. Combust fuel as an oxidizer. That is, in the combustion chamber R, high-temperature combustion gas is generated by burning the fuel injected from each burner x2.

Also, in the combustion chamber R, combustion ash is generated as the fuel burns. Most of this combustion ash falls below the combustion chamber R and is collected, but a part of it rises together with the combustion gas and flows from the combustion chamber R toward the exhaust port E in the boiler. The high-temperature combustion gas functions as a heat source for generating water vapor in the boiler, but also functions as a powder carrier for transporting the combustion ash toward the exhaust port E.

The superheater x3 is a heat exchanger for further heating the saturated steam generated in the boiler, and is provided directly above the combustion chamber R in the internal space of the boiler surrounded by the boiler wall x1. The superheater x3 generates superheated steam having a heat energy higher than that of the saturated steam by exchanging heat with the combustion gas.

The reheater x4 is a heat exchanger for reheating the steam used to drive the steam turbine, and is provided immediately after the bent portion x6 in the internal space of the boiler. There are various configurations of steam turbines in power plants, and some power plants are equipped with a steam turbine for low pressure in addition to a steam turbine for high pressure. The reheater x4 reheats, for example, the steam used to drive the high-pressure steam turbine before supplying it to the low-pressure steam turbine.

The economizer x5 is a heat exchanger (preheater) also called an economizer, and is provided on the downstream side of the reheater x4 in the flow direction of the combustion gas in the internal space of the boiler. This coal saver x5 heats (preheats) the boiler feed water before vaporization in order to improve the thermal efficiency of the boiler.

Here, there are various configurations of heat exchangers in the boiler. The heat exchanger shown in FIG. 1, that is, the superheater x3, the reheater x4, and the economizer x5 is merely an example. The boiler in the present embodiment may include, for example, an economizer x5 that preheats the boiler water supply, and an air preheater that preheats the combustion air taken in from the outside air and supplies it to the combustion chamber R. ..

The bent portion x6 is a portion in the internal space of the boiler where the flow path area of the combustion gas generated in the combustion chamber R is the narrowest, and the flow direction of the combustion gas changes from an ascending flow to a descending flow. The bent portion x6 is also a portion to which the combustion ash contained in the combustion gas easily adheres.

For such a boiler combustion furnace X, the furnace monitoring device A according to the present embodiment includes an infrared camera 1, a control device 2, an analysis device 3, and a monitoring panel 4, as shown in FIG.

The infrared camera 1 is an imaging device whose imaging location is a predetermined monitoring location in the combustion furnace X (fire furnace), and photographs combustion ash adhering to the monitoring location. That is, the infrared camera 1 detects infrared rays radiated from the monitoring point, generates a two-dimensional thermal image of the monitoring point as a monitoring image, and outputs the two-dimensional thermal image to the control device 2.

Such an infrared camera 1 excludes the flame radiated into the combustion furnace X from the burner x2, for example, and captures the combustion ash. That is, the infrared camera 1 detects only infrared rays in a specific wavelength band that does not include infrared rays in the wavelength band in which the flame is emitted in the infrared region of the electromagnetic wave. Such a surveillance image (thermal image) of the infrared camera 1 is a two-dimensional image that faithfully shows the state of the surveillance portion where the flame does not act as a disturbance.

Such a monitoring image (thermal image) is, for example, a black-and-white image in which the brightness value increases as the amount of combustion ash adhered increases. That is, the monitoring image (thermal image) is a two-dimensional image in which the amount of combustion ash adhered correlates with the brightness value. The brightness value is close to black. As such an infrared camera 1, for example, an in-core surveillance camera manufactured by Lumasense (Lumasense Technologies, Inc.) can be adopted.

Here, the monitoring points in the present embodiment are, for example, the boiler wall x1 in the vicinity of the burner x2, that is, the periphery of the burner x2 (the wall surrounding the burner x2 in the boiler wall x1), the superheater x3, the bent portion x6, and the reheater. One or more of x4 and the coal saver x5. In particular, the boiler wall x1 and the superheater x3 in the vicinity of the burner x2, which are a part of the combustion chamber R, are places where the combustion ash easily adheres in the internal space of the boiler, that is, in the flow path of the combustion gas and the combustion ash.

As shown in FIG. 2, a monitoring window x7 for monitoring the state of the burner x2 is provided on each of the pair of boiler walls x1 (side wall) intersecting with the pair of boiler walls x1 provided with the burner x2. Often. When the boiler wall x1 in the vicinity of the burner x2 is used as the monitoring point, the infrared camera 1 captures, for example, the boiler wall x1 in the vicinity of the burner x2 through the monitoring window x7.

That is, when the boiler wall x1 in the vicinity of the burner x2 is used as the monitoring point, the infrared camera 1 can be installed without any processing such as providing an opening in the boiler wall x1. Therefore, according to the present embodiment, the infrared camera 1 can be easily installed in the existing boiler.

The above-mentioned infrared camera 1 is installed so that such a monitoring point has an angle of view. Although one infrared camera 1 is shown in FIG. 1, the number of infrared cameras 1 is not limited to one. That is, an infrared camera 1 may be provided for each monitoring location, or a plurality of monitoring locations may be simultaneously imaged by one infrared camera 1.

The control device 2 controls the infrared camera 1 and captures a surveillance image (thermal image) input from the infrared camera 1. That is, the control device 2 controls the shooting timing of the surveillance image (thermal image) in the infrared camera 1. Further, the control device 2 captures the surveillance image (thermal image) taken at the shooting timing specified by itself from the infrared camera 1 and provides the analysis device 3. Such a control device 2 is a computer that functions based on a control program stored in advance. That is, the control device 2 is a main storage device such as a CPU (Central Processing Unit), a RAM (Random Access Memory) or a ROM (Read Only Memory), and an auxiliary storage such as an SSD (Solid State Drive) or an HDD (Hard Disc Drive). It is a kind of computer composed of devices and the like.

The analysis device 3 evaluates the adhesion state of combustion ash at the monitoring location based on the monitoring image (thermal image). That is, the analysis device 3 acquires the surveillance image (thermal image) output by the infrared camera 1 via the control device 2, and performs predetermined image processing on the surveillance image (thermal image) to deposit combustion ash. Evaluate the quantity t. The analysis device 3 constitutes an evaluation device together with the control device 2 described above.

Such an analysis device 3 is a computer that performs image processing on a monitoring image (thermal image) based on an analysis program stored in advance and evaluates the accumulated amount t of combustion ash based on the result of the image processing. .. That is, the analysis device 3 is a main storage device such as a CPU (Central Processing Unit), a RAM (Random Access Memory) or a ROM (Read Only Memory), and an auxiliary storage such as an SSD (Solid State Drive) or an HDD (Hard Disc Drive). It is a kind of computer composed of devices and the like. For example, the analyzer 3 stores in advance a deposit amount table showing the relationship between the brightness value of the monitoring image (thermal image) and the deposit amount t of the combustion ash, and by using this deposit amount table, the combustion ash is deposited. Evaluate the quantity t. The analysis device 3 will be described in detail in the operation description described later.

The monitoring panel 4 is provided in a monitoring room for monitoring the operation of the boiler. This monitoring panel 4 is provided to an observer who monitors the operation of the boiler, and various information (boiler operation information) indicating the operating state of the boiler is posted. Such a monitoring panel 4 notifies about combustion ash based on the evaluation result of the analysis device 3 as one of the boiler operation information. That is, the monitoring panel 4 is a notification device in the present embodiment.

Next, the operation of the furnace monitoring device A according to the present embodiment will be described in detail with reference to FIG.

In this furnace monitoring device A, the control device 2 instructs the infrared camera 1 to acquire a monitoring image (thermal image) based on a preset time schedule. That is, the control device 2 outputs a monitoring image (thermal image) acquisition instruction to the infrared camera 1 at a time set based on the control program. Then, the infrared camera 1 sequentially acquires the monitoring image (thermal image) of the monitoring location based on this acquisition instruction (step S1).

Then, the surveillance image (thermal image) acquired by the infrared camera 1 in this way is input from the infrared camera 1 to the analysis device 3 via the control device 2. The analysis device 3 performs image processing, that is, filter processing, on the monitored image (thermal image) (step S2). This filtering process removes noise contained in the surveillance image (thermal image).

Then, the analyzer 3 acquires the luminance value of the monitoring image (thermal image), and searches the accumulated amount table stored in advance using this luminance value, so that the accumulated amount of combustion ash corresponding to the luminance value is accumulated. Acquire t (step S3). Then, the analysis device 3 determines whether or not the accumulated amount t exceeds the limit value by comparing the accumulated amount t thus acquired with the evaluation threshold value Tref stored in advance (step S4). ).

Then, when the determination result in step S4 is "Yes", the analysis device 3 outputs an alert to the monitoring panel 4 (step S5). This alert alerts the observer regarding the adhesion of combustion ash and is notified as audio or / and video. The observer can know from such an alert that the combustion ash is attached beyond the limit value.

According to the present embodiment as described above, since the accumulated amount t of the combustion ash is automatically evaluated based on the monitoring image (thermal image) of the infrared camera 1, the evaluation of the adhesion state of the combustion ash is more effective than before. It is possible to provide.

The present disclosure is not limited to the above embodiment, and for example, the following modifications can be considered.
(1) In the above embodiment, the combustion furnace X of the boiler is set as the furnace to be monitored, but the present invention is not limited to this. The present disclosure can be applied to various furnaces other than the combustion furnace X of the boiler.

(2) Although the infrared camera 1 for capturing the combustion ash by excluding the flame radiated from the burner x2 into the combustion furnace X is used, the present disclosure is not limited to this. When the boiler wall x1 near the burner x2 is used as the monitoring point, it is necessary to remove the influence of the flame, but since it is not necessary to consider the influence of the flame for other monitoring points, a general infrared camera is used. You may use it.

(3) Further, in the above embodiment, the infrared camera 1 excluding the flame of the burner x2 is used, but the present disclosure is not limited to this. For example, a general infrared camera may be used as the image pickup device by providing the analysis device 3 with a function of excluding the flame of the burner x2.

(4) In the above embodiment, the control device 2 and the analysis device 3 are provided as separate devices, but the present disclosure is not limited to this. That is, the function of the control device 2 and the function of the analysis device 3 may be integrated into a single device.

X Combustion furnace (fire furnace)
x1 boiler wall
x2 burner
x3 superheater
x4 reheater
x5 economizer
x6 bend
x7 Monitoring window R Combustion chamber E Exhaust port 1 Infrared camera (imaging device)
2 Control device (evaluation device)
3 Analytical device (evaluation device)
4 Monitoring panel (notification device)

Claims

An imaging device that captures the combustion ash adhering to the monitoring points in the furnace, and
An evaluation device that evaluates the adhesion state of the combustion ash based on the monitoring image output by the image pickup device, and an evaluation device.
A furnace monitoring device including a notification device for notifying the combustion ash based on the evaluation result of the evaluation device.
The furnace monitoring device according to claim 1, wherein the furnace is a boiler combustion furnace.
The monitoring location is a superheater, the furnace monitoring device according to claim 2.
The furnace monitoring device according to any one of claims 1 to 3, wherein the monitoring location is around a burner provided in the furnace.
The furnace monitoring device according to any one of claims 1 to 4, wherein the image pickup device is an infrared camera that captures the combustion ash by excluding flames.